Question

rewrite the definition as a biconditional statement. two angles are vertical angles when their sides form two pairs of opposite rays.

Explanation:

Step1: Recall biconditional structure

A biconditional statement has the form "P if and only if Q", where P and Q are statements. Here, let P be "Two angles are vertical angles" and Q be "Their sides form two pairs of opposite rays".

Step2: Form the biconditional

Combine P and Q using "if and only if" to get the biconditional.

Answer:

Two angles are vertical angles if and only if their sides form two pairs of opposite rays.